Shortly after United Airlines Flight 1214 took off from Raleigh-Durham International Airport on Wednesday morning, the pilot called the control tower and suggested there had been an assault onboard, airport spokesperson Mindy Hamlin told The Associated Press.

Turns out, two flight attendants got into a disagreement on the way to Chicago, so the plane returned to the airport. The Boeing 737-800 plane, which had 52 passengers on board, landed at 6:40 a.m., The News & Observer in Raleigh reported. Police in Raleigh-Durham did not arrest anyone and concluded that no blows were exchanged, according to the AP.

"One flight attendant had crossed their leg and accidentally brushed the other person, and it was not intentional,” Hamlin told The News & Observer. "It appears there was a disagreement before that, that became elevated."

The flight was re-staffed and later continued to Chicago O'Hare.

"We apologize to our customers for the delay and are compensating them for the inconvenience," United said in a statement.

Some passengers were put on other flights, airline spokesperson Christen Davis told the AP.

The airline says it's also conducting an internal review, though Davis noted that the argument was not physical.